Digital Commons at Penn State

MIDI, which stands for "musical instrument digital interface," is an electronic music format which contains a list of notes to play and descriptions of the instruments to play them on. Since MIDI files contain lists of musical notes, and not actual sounds, they are much smaller than WAV or AIF files of the same duration.

However, MIDI files can only create music, not sound effects or speech. It is not possible to convert a WAV or AIF file into a MIDI file, just as it is not possible to write sheet music that describes the sound of a lion's roar or of a person's voice.

It is possible to convert a MIDI file into a WAV or AIF file, however.